Virtually all bicycles are equipped with pneumatically-inflated tires. Conventionally, these tires are inflated by attaching a pump to an air-admitting valve secured to the inner tube of the tire. When the tire pump is manually activated, air will pass from the tire pump, through the valve, and into the inner tube. Conventional hand-held bicycle tire pumps are often very cumbersome in the inflation of the tire. As high pressures are received within the interior of the tire, it becomes increasingly difficult to pump the manual tire pump so as to achieve the desired pressures. Modern bicycle tires often require pressures in excess 100 p.s.i. in order to obtain the desired hardness. The application of the proper forces onto the tire pump can often be very exhausting to the cyclist.
In order to achieve the optimum bicycle tire inflation pressure, the cyclist will repeatedly increase the amount of pressure within the tire. If the amount of pressure within the inner tube of the tire should fall below a desired level, then the tire will be too flat for proper usage on the road. Optimum peddling efficiency deteriorates when there is too little pressure within the tire. As a result, the cyclist will inefficiently pump the pedals of the bicycle in order to propel himself or herself along the bicycle pathway.
In other circumstances, it is not desirable to have an excess amount of inflation pressure within the tire. If too much pressure was received within the tire, then there is the risk of bursting the tire. Additionally, excess inflation will reduce friction between the surface of the tire and the road. This reduced friction will enhance the risks of sliding and hydroplaning and will reduce traction. As a result, most bicycle tires are provided with recommended inflation pressures in a desired range.
Heretofore, the only effective technique for determining the amount of pressure within the tire is the application of tire pressure gauges. These tire pressure gauges are similar to those used on automotive tires. The bicycle tire pressure gauge includes an inlet valve that is secured over the tire valve so that a small amount of air will pass into the gauge. The gauge will then suitably react so as to provide a visual indication to the user to the amount of pressure within the tire. If there is too little pressure within the tire, then the cyclist must, once again, pump the tire to the desired pressure. It is typical that a small amount of pressure will continually leak from the tire during continued use or over extended periods of time.
Unfortunately, whenever the tire pressure gauge is applied to the valve of the tire, there is a risk that a large amount of pressure is lost. Most cyclists have experienced the frustrating problem where the pressure in the tire is lost because of an inadequate application of the tire pressure gauge to the valve of the tire. Often, an excess amount of the air will leak from the tire during the application of the pressure gauge onto the tire valve. So as to accommodate this problem, cyclists often will attempt to overinflate the tire so as to accommodate the small amount of leakage that will occur when the pressure is being measured. In many circumstances, cyclists will resist the need to continually monitor tire pressure in order to avoid the accidental loss of pressure from the tire. The pumping of the tire is considered a very undesirable activity by the cyclist.
In the past, various U.S. patents have issued relating to bicycle tire pressure gauges. For example, U.S. Pat. No. 5,505,012, issued on Apr. 2, 1996, to Rabizadeh, discloses a tire pressure monitoring device that includes a ball disposed within a tube which has an opening, at one end, in communication with the interior of the tire. The tube has a transparent window along its length to allow the position of the tire pressure ball to be visualized. The transparent window has graduations calibrated to allow the tire pressure to be determined by the position of the ball.
U.S. Pat. No. 4,919,600, issued on Apr. 24, 1990 to Yang, discloses a tire pump with a pressure gauge including a cylinder having a piston head slidably provided in the cylinder. A pressure measuring device with a pressure indicating element is disposed at a front end of the cylinder so that the pressure indicating element is readable through a peep hole in the cylinder. The pressure measuring device interconnects at an outlet of the cylinder. A bypass tube with a check valve is disposed beside the pressure measuring device so that air pressurized by the piston head blows out from the outlet through the bypass tube. The pressurized air also flows through the air holes in order that the pressure within the pumped tire can be read from the pressure indicating element of the pressure measuring device through the peep hole.
U.S. Pat. No. 6,196,807, issued on Mar. 6, 2001 to S. Wu, describes a pressure gauge of a tire pump which includes a chamber and a pressure indicator movably received in the chamber. The pressure indicator has a tube with a head portion attached to a first end thereof and a receptacle defined in a second end thereof. The head portion is in slidable contact with an inner periphery of the chamber and the tube is not in contact with the inner periphery of the chamber.
U.S. Pat. No. 6,132,189, issued on Oct. 17, 2000 to A. R. Ward, teaches a combined bicycle tire and air suspension pump with a removable pressure gauge. U.S. Pat. No. 6,558,129, issued on May 6, 2003 to L. P. Wang, also discloses an air pump having a pressure gauge thereon. Similarly, U.S. Pat. No. 4,120,614, issued on Oct. 17, 1978 to P. C. Bouder, discloses a hand bicycle pump with a pressure preselection and a display means. Additionally, and furthermore, U.S. Pat. No. 5,964,577, issued on Oct. 12, 1999 to L. Chuang, discloses a hand air pump with a pivotable pressure gauge.
In the field of tire hardness testers, there is provided a patent relating to the testing of automotive tires in the form described in U.S. Pat. No. 4,348,891 of Sep. 14, 1982. This patent describes a tire hardness tester wherein a support member movably supports a durometer which is connected to means for controlling the rate of the descent of such a durometer to provide a constant predetermined force for measuring the hardness of a tire tread. A tire supports the tire in such way that it is in alignment with the durometer.
It is an object of the present invention to provide a bicycle tire hardness testing device that is a simple and easy technique for checking on the correct hardness of the tire.
It is another object of the present invention to provide a bicycle tire hardness testing device which is small, light and easy to transport.
It is another object of the present invention to provide a bicycle tire hardness testing device which correlates with the pressure in the tire without the need for using a pressure gauge secured to the inflation valve of the tire.
It is another object of the present invention to provide a bicycle tire hardness device which is of greater reliability than conventional valve-connected devices.
It is a further object of the present invention to provide a bicycle tire hardness testing device which is easy to manufacture and relatively inexpensive.
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims.